It's pretty much the perfect mouse, IMO, to the point that I built up a back stock by hoarding new and open box on eBay. But there are two main problems:
1) The the microswitches go bad after a couple years. It's possible to replace them, but it's tedious and you run a very real risk of damaging the PCB (as I have already done).
2) The dongle is USB Type-A only. Logitech actively refused to make a USB-C unifying receiver. I assume they wanted to shift to bluetooth but they still made unifying receiver devices for years and years after bluetooth was everywhere, so I dunno.
As far as newer iterations, the Anywhere MX 2S is somewhat tolerable, but it has a built-in battery which must be charged every couple of months, which is annoying. All of the newer Anywhere MX mice are even worse because they changed the basic functionality/features of the mouse with each revision. Oh, yes and they cost $90 (!) retail now.
So basically one of my side-projects, one of these days, is going to be to try building an open source Anywhere MX clone. Should be a fun yet challenging endeavour. I know there are a bunch of online communities making their own keyboards from scratch and at great expense, is there such a thing for mice?